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Light And Distance From The Big Bang
If the light from the big bang reaching me took 14 billion years then what would be/been the situation in one billion years time or one billion years ago.
So ( ignoring any expansion of the universe. ) if our distance to the big bang remains constant the light would have reached us
earlier in 13 billion years ( one billion years ago ) and therefore later in 15 billion years ( in one billion years time ).
This is becoming confusing . Let me see we are looking at an event which occurred 14 billion years ago. So what would we be looking at in one billion years time. It can't be the same event because that would have long passed. So we would be looking at the situation one billion years after the big bang.
So in 14 billion years time we would see what we are seeing now.
And in 15 billion years ??????
Can you clarify the situation ?
15:33 Sat 19th Jan 2013
So ( ignoring any expansion of the universe. ) if our distance to the big bang remains constant the light would have reached us
earlier in 13 billion years ( one billion years ago ) and therefore later in 15 billion years ( in one billion years time ).
This is becoming confusing . Let me see we are looking at an event which occurred 14 billion years ago. So what would we be looking at in one billion years time. It can't be the same event because that would have long passed. So we would be looking at the situation one billion years after the big bang.
So in 14 billion years time we would see what we are seeing now.
And in 15 billion years ??????
Can you clarify the situation ?
15:33 Sat 19th Jan 2013
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For more on marking an answer as the "Best Answer", please visit our FAQ.You can't isolate a consequence from its cause. Time and space are a consequence of the 'big bang'.
The light we see from the initial event is a fraction of that which permeates the universe, the part that coincidently is now reaching us at any given instant in time.
The 'big bang' is just the beginning of an ongoing process of expansion and cooling. The universe was hotter and denser in the past and continues to expand and cool.
We cannot point to a place where the 'big bang' took place. It is (and was) all around us and we are in it. The 'big bang' was and is . . . the place.
The light we see from the initial event is a fraction of that which permeates the universe, the part that coincidently is now reaching us at any given instant in time.
The 'big bang' is just the beginning of an ongoing process of expansion and cooling. The universe was hotter and denser in the past and continues to expand and cool.
We cannot point to a place where the 'big bang' took place. It is (and was) all around us and we are in it. The 'big bang' was and is . . . the place.
The big bang supposedly lasted for a few seconds and it has taken 14 billion
years to reach us, but that moment has passed . That 'image' has passed us so to speak so how can we still ' see it ' ?
If I see lightning in the sky I can never see it again . Its light may go on into space and could be seen/detected by other planets but never by me.
Even allowing for an error in the 14 billion that doesn't matter what we see
at any moment in time can never be seen again.
The other day on the TV they said they were lucky they had seen a super nova ( mini big bang ) thousands of light years away and said they may have to wait several more years to see another one. There was no question of going back the next day and seeing it again. So how can they see a super super duper duper bang again and again. Even if space is curved I would still have to wait a long time for it to come round again and if I blinked I would miss it.
I'm sorry for banging on about it ( parden the pun ) but I just don't get it.
years to reach us, but that moment has passed . That 'image' has passed us so to speak so how can we still ' see it ' ?
If I see lightning in the sky I can never see it again . Its light may go on into space and could be seen/detected by other planets but never by me.
Even allowing for an error in the 14 billion that doesn't matter what we see
at any moment in time can never be seen again.
The other day on the TV they said they were lucky they had seen a super nova ( mini big bang ) thousands of light years away and said they may have to wait several more years to see another one. There was no question of going back the next day and seeing it again. So how can they see a super super duper duper bang again and again. Even if space is curved I would still have to wait a long time for it to come round again and if I blinked I would miss it.
I'm sorry for banging on about it ( parden the pun ) but I just don't get it.
I have just read the related posts and what they are saying is we can detect the residual radiation from the big bang which is not seeing it as implied in the Stargazing programmes. However how do they know this radiation is from the big bang and not from all the other explosions in space that have and are still taking place and where does the 14 billion come from.
Supernova are localised phenomena. They take place in individual stars and the radiation they emit emanates from a specific time and location, an exploding star in a pre-existing universe. The 'big bang' is a different animal altogether. The 'big bang' is the origin of both time and space, not an event that took place at some point within it.
Technically, the 'big bang' was rendered invisible from the start. Due to the initial density of the universe, light was continually emitted and reabsorbed by surrounding matter. Only after the universe had expanded and cooled over many thousands of years did the universe become transparent to the light which is distributed more or less evenly throughout the universe and which now comprises the cosmic microwave background radiation.
As explained above, we can not directly observe the 'Big bang'. We are only witness to its remnants that permeate the universe it gave birth to and which point to its beginning. The portion of that remnant we observe at any given moment as the cosmic microwave background radiation, is the tiny fraction that at any given moment originated from the distance corresponding to the time we see it.
Technically, the 'big bang' was rendered invisible from the start. Due to the initial density of the universe, light was continually emitted and reabsorbed by surrounding matter. Only after the universe had expanded and cooled over many thousands of years did the universe become transparent to the light which is distributed more or less evenly throughout the universe and which now comprises the cosmic microwave background radiation.
As explained above, we can not directly observe the 'Big bang'. We are only witness to its remnants that permeate the universe it gave birth to and which point to its beginning. The portion of that remnant we observe at any given moment as the cosmic microwave background radiation, is the tiny fraction that at any given moment originated from the distance corresponding to the time we see it.
I have always had a hard time grasping this .
At the instant of the ' Big Bang ' space /the universe expanded at a rate far outstripping the speed of light .
Therefore that is the reason why we can observe events going back billios of years - because the light from those events are only just reaching us .
Is that total rubbish ?
At the instant of the ' Big Bang ' space /the universe expanded at a rate far outstripping the speed of light .
Therefore that is the reason why we can observe events going back billios of years - because the light from those events are only just reaching us .
Is that total rubbish ?